1. Field of the Invention
This invention relates to tools used for shaping and cutting tile and, more particularly, to tools used to chipping natural stone tile.
2. Description of Related Art
Natural stone tile is widely used for decorative floors. Natural stone tile may be manufactured from a variety of naturally-occurring materials, such as marble, granite, slate, flagstone, onyx, and sandstone. As is the case with denim jeans, it has become fashionable to use natural stone tile which has a used, or rustic appearance. Natural stone tile is often given a rustic appearance by placing the tile in a large drum filled with small stones. When the drum is rotated, the stones abrade the edges of the tile, giving the edges a rounded and worn appearance. This is obviously an expensive, labor-intensive process, which can result in a near doubling of the price of the tile. The increase in cost is related not only to the additional labor required to treat the tile, but is also related to the cost of the equipment required by the rustication process. Because natural stone tile is of generally uniform composition throughout its entire thickness, the rustication process does not remove or damage a protective coating, such as the glass layer that is present on fired ceramic tile.
What is needed is a relatively inexpensive, portable, simple-to-use tool which can be employed by an installer of tile to abrade the edges of each piece of tile prior to the installation thereof. It would be desirable that such a tool would provide an appearance similar to that achieved by the more costly rotating drum process. Such a tool would also have a flexibility advantage over use of the rotating drum process, as small quantities of tile could be treated in a cost-effective manner.
The present invention provides both a method and an apparatus, or tool, for chipping the edges of natural stone tile in order to give the tile a used or rustic appearance. The tool comprises an axially-rotatable, cylindrical member having an array of studs affixed or embedded in the cylindrical surface. A drive shaft, affixed to one end of the cylindrical member, may be inserted within the chuck of a powered drill motor or other similar powered device. A handle is rotatably coupled to the opposite end of the cylindrical member. For a preferred embodiment of the invention, the handle consists of a tubular sleeve which is rotatably mounted on bearing races over a support shaft that is rigidly and coaxially affixed to the cylindrical member. Alternatively, the cylindrical member may have a hollow cylindrical recess at the handle end thereof, and a handle may be rotatably mounted within the recess in bearing races.
The studs may be affixed to the cylindrical member in various ways. For one embodiment of the invention, the studs are domed globs of welded material. For another embodiment, the studs are tungsten carbide inserts, each of which is mounted within a recess formed within the cylindrical member. The inserts may be affixed within the recesses with brazing compound or with an epoxy adhesive. For yet another embodiment of the invention, the studs are integral with the cylindrical member, being, for example, investment cast, sand cast, or forged as a unit.
In order to use the tool, the drive shaft is secured within the chuck of a drill motor or other similar device designed to provide powered rotary motion to a shaft. With the operator holding both the drill motor and the handle of the chipping tool, the rotating studded cylindrical member is moved along and against the edge of a piece of natural stone tile. The edge of the tile is thereby chipped or abraded. The amount of material removed from the edge may be controlled by varying the amount of time and pressure. The angle can be varied over several strokes, thereby imparting a roughly curved edge to the tile. Using the tool and method, up to three 12-inch-square tile may be treated per minute.